something i have been playing with this last week
vactrol type isnt fussy i am using NSL32 but could just as well be
vtl5c3, A slow closing vactrol like a vtl5c4 could be interesting also
the P2 connector goes to a B100k pot pin 2 is the wiper just reverse 1 and 3 if left / right is wrong way round . note with the pot in the centre and no cv input there is no output.or at least very little
CV input can be from an LFO output +5 to -5 volts though going to the rails will not hurt anything.
T1 and T2 adjust the sensitivity for the vactrols you can get them pretty good just by watching the panel leds PD-L / PD-R while adjusting P2 for the supplied voltage though the actual vactrol response is slightly different to normal leds so also use your ears
anyway hope someone can use this